The present invention relates to a lighting device, in particular a floodlight such as a sealed lamp embedded in the ground.
It is already known in the art a lighting device, in particular a floodlight such as a sealed lamp embedded in the ground, emitting a directional frontward directed light beam, said prior device comprising:
1. an optical reflector,
2. a light source installed at the focus of the optical reflector,
3. an electric power supply unit for power supplying the light source,
4. a disc element supporting a translucid material for allowing light to be outward directed.
The above mentioned elements are arranged in a sealed casing provided for use in outside environments, in particular adapted to be embedded in the ground in a receiving well defining a volume suitable to house the device therein.
A drawback of this prior lighting device is constituted by the comparatively high heating of the translucid material contacting the outside environment and provided for transmitting the optical light beam.
This heating, which is essentially due to the heat emitted by the light source, generates very high temperatures which are very dangerous for persons susceptible to contact such an unprotected surface.
This would be particularly objectable as the lighting device is installed at places available to the public.
Standardized devices have been designed for controlling the above type of danger, and the standardized devices, in particular, has been standardized depending on their use conditions.
On the other hand, since it is essential to have the surface of the lighting device contacting the outside environment as smooth as possible for preventing, for example, any accumulation of powder, liquids and so on, susceptible to obstruct the emitted optical light beam, it would not be suitable to prevent the hot surface of the lighting device from being accessed by using a mechanical means such as a protective grid.